Hitachi Set Free mini-HNRQ1 Series, Service Manual

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31
INSTALLATION
4.1 General Check
(1) Make sure that the field-supplied electrical components (main power switches, circuit breakers, wires,
conduit connectors and wire terminals) have been properly selected according to the electrical
characteristics indicated in the table 4.1. Make sure that the components comply with the local national
standards and rules.
●
The power sources for the indoor unit and outdoor unit should be supplied respectively.
●
Supply electrical power to each outdoor unit. An ELB (Earth Leakage Breaker), fuse and main switch
should be used for each outdoor unit. If not, it will be cause of fire or electrical shock.
(2) Ensure that the power supply voltage is within ±10% of the rated voltage. If the power supply voltage is
too low, the system cannot start due to the voltage drop.
(3) Check the size of the electrical wires.
(4) Ensure that the ground wiring for the outdoor unit and indoor unit are connected. If not, it will be cause
of fire or electrical shock.
(5) Communication cabling shall be a minimum of 0.75mm
2
, 2-Conductor, Stranded Copper. Shielded cable
must be considered for applications and routing in areas of high EMI and other sources of potentially
excessive electrical noise to reduce the potential for communication errors. When shielded cabling is
applied, proper bonding and termination of the cable shield is required as per guidelines. Plenum and riser
ratings for transmission cables must be considered per application and local code requirements.
●
In case of where the power source for the air conditioning is supplied from the same power
transformer as the device with high electricity consumption*.
●
In case of where the power supply wiring for the device* and for the air conditioning are located close
to each other.
* Example: Lift, container crane, rectifier for electric railway, inverter power device, arc furnace, electric
furnace, large-sized induction motor, and large-sized switch.
In the instances mentioned above, an induction surge of the power supply wiring for the air conditioning
could occur due to a rapid change in electricity consumption of the device and activation of the switch.
Therefore, check
the field regulations and standards before performing electrical work in order to protect
the power supply wiring for the air conditioning.